(1) Field of the Invention
This invention relates to indexing devices of the type having a plurality of cards kept in file between a base member of a case and a cover member pivotally secured to said base member, and more particularly to indexing devices designed such that one can open the device to any desired page together with the cover member by simply operating one of a plurality of operating arms provided inside said cover member.
(2) Description of the Prior Art
The more conventional and popular type of indexing devices comprise generally a base member, a cover member pivotally secured thereto, and a plurality of cards kept in file between the base and cover members. A selection pawl is slidably, mounted to the cover member for selecting a desired card from the plurality of cards and holding the selected card in position. An alphabetic array of letters or other index signs is provided on the cover member corresponding to pre-established possible positions of the selection pawl. A separate locking mechanism is provided between the cover member and base. To operate such devices, however, the user must perform two different operations; that is, selecting a card with the selection pawl and opening the case cover with the separate locking mechanism.
Also known are indexing devices of the type in which a plurality of selectors are associated with the respective cards or pages of the index. The selectors are positioned in the base member and the selectors are interlocked with the cover locking mechanism so that one can accomplish both card selection and cover opening simultaneously by operating one of said selectors. However, such devices also involves some serious drawbacks. Since the card selecting mechanism is provided in the base, the size of the base is inevitably enlarged in comparison with the card size. Also, the internal mechanism is typically complicated and the number of necessary parts is large thus resulting in a greater amount of labor and elevated cost for manufacture.